Granted Patent
Utility
US 4,838,913 · App. 07/154,301
Double column air separation process with hybrid upper column
Inventors:
Richard A. Victor, Michael James Lockett
Patented Case
View Patent ↗
Granted: Jun 13, 1989
Filed: Feb 10, 1988
Inventors
Richard A. Victor
Michael James Lockett
Assignee (at issue)
Union Carbide Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.